Dolphins are hunted for their teeth in the South Pacific

You’ve heard of The Cove and the long history of the dolphin “drive hunts” in the Japanese coastal town of Taiji. Boats, nets, and loud noises herd dolphins into a small cove where their escape back into the sea is prevented. They are killed for their meat, and a few are captured for transport to aquariums and dolphinariums elsewhere. But Japan is not the only culture with a long history of dolphin drive hunts. In the Solomon Islands, villagers have participated in the tradition off and on at least for the last several hundred years.

While many villages in the Solomon Islands, a nation that’s part of the British Commonwealth that consists of part of the Solomon Islands archipelago east of Papua New Guinea, seem to have ended the practice, others have not. But it’s not the meat they’re after, at least not primarily. It’s the teeth.

It’s difficult to ascertain just when and where the drive hunts were carried out over the years, and how many of which species were taken, but that’s what researchers Marc Oremus, John Leqata, and C. Scott Baker wanted to figure out.

Unlike in other parts of the world where motors have replaced oars and paddles, the drive hunts in the Solomon Islands retain their more traditional roots. Twenty to thirty canoes take to the water, and when they find a pod of dolphins, hunters clap round stones together underwater. The sounds act as a sort of acoustic barrier, and while the hunters maneuver their canoes into a U-shape, the dolphins are forced toward shore, where they are killed.

Also unlike in other parts of the world (and even in other parts of the Solomon Islands), this sort of traditional drive hunt is not related to the more recent live-capture of Indo-Pacific bottlenose dolphins for the aquarium trade. Instead, the hunters focus mainly on spinner dolphins and pantropical spotted dolphins; the bottlenose dolphins are larger and apparently do not respond to the more traditional driving techniques. While the meat from the dolphins that are captured does get consumed both within the hunting villages and after being sold on other islands, the “main objective,” according to Oremus and his colleagues writing this week in the Royal Society’s journal Open Science, is to collect teeth for their use as “traditional currency, bride price, adornment and, more recently, for cash sale.”

The only villages still participating in drive hunts are Lau-speaking ones on the island of Malaita, though the meat does get consumed elsewhere — especially on Guadalcanal. When the researchers met with elders in the village of Fanalei to obtain an oral history — and compared their notes with a few previously published accounts of the hunts from other researchers — they learned that the hunts did not initially occur each year, but were instead sporadic. Then sometime during the middle of the 1800s, the hunts stopped, perhaps owing to the introduction of Christianity to the islands. In 1948 the hunts were revived in Fanalei, and by 1958 had been introduced in at least five other villages on the island by Catholic religious leaders. The researchers think that hunts were widely distributed over time, with several years passing between successive hunts. But then in 1964, the hunts in Fanalei “increased markedly,” with several thousand dolphins being caught every year.

Then, in 2010, the Earth Island Institute, a US-based NGO, offered financial compensation to several Malaita villages in exchange for ending their drive hunts. A memorandum of understanding was signed with representatives from Fanalei, Bitama, and Walande villages (the latter villages were offered money even though they had already stopped hunting). But the agreement broke down, and on January 22, 2013, the Fanalei communities resumed their traditional hunts. That day they brought in 700 dolphins, followed several days later by another 300.

It isn’t clear what sparked the breakdown in the agreement, but now that the drive hunts have resumed, Oremus, Leqata, and Baker’s goal was to try to confirm both the number and species that are being killed on Fanalei’s resumed drive hunts. Oremus and Leqata visited Fanalei in March 22, 2013, with Leqata acting as translator. In addition, they collected samples of meat found in village kitchens, skin and bone from dumped carcasses, and teeth from recent hunts provided by villages.

From discussions with Fanalei hunters, the researchers determined that the species referred to as unubulu was the pantropical spotted dolphins, the one called raa was the spinner dolphin, and robo manole was most likely the common bottlenose dolphin (but might also have been the smaller Indo-Pacific bottlenose), by far the least likely species to wind up dead on the shores of Malaita Island. Genetic data from the tissue samples confirmed the identities of both the unubulu and raa species; no samples were taken from any carcass believed to be a bottlenose.

In addition, a hunter named Albert Balei kept detailed records of each of the hunts throughout the 2013 season. In that year alone, more than 1,500 spotted dolphins and 150 spinners were caught, plus another 15 robo manole.

By collecting additional information from Balei as well as from other sources, the researchers estimate at least 15,454 dolphins were killed by Fanalei villagers for the years 1976 through 2013. That’s a gross underestimate, though. Data for at least 16 hunting years are missing from their dataset, as well as for all villages besides Fanalei. While they weren’t able to identify any obvious trends from their data, it seems as if low catch years predictably follow years of plenty, perhaps because of local depletion following intensive hunting. It is also possible, however, that a glut of teeth following a good year would lead to a reduced hunting effort the next.

Dolphin teeth from individuals hunted in 2013: (a) spotted dolphin; (b) spinner dolphin and (c) young "robo manole," probably referring to common bottlenose dolphin.

Dolphin teeth from individuals hunted in 2013: (a) spotted dolphin; (b) spinner dolphin and (c) young “robo manole,” probably referring to common bottlenose dolphin.

One possible explanation for the breakdown in the MOU with the Earth Island Institute is that the market value of dolphin teeth went up. Though Malaita is the main source of dolphin teeth and meat in the area, they are also used on other islands both within Solomon Islands and elsewhere. Stopping the hunt therefore increased demand, and the consequences of that agreement reverberated far beyond the villages in which it was made. Adjusting for inflation is tricky, but the researchers estimate that you could buy a single dolphin tooth in 1964 for about one US nickel. By 2013, a tooth was worth around 68 cents, or around 1,300% more.

Together, the data suggest that dolphins are being killed in the Solomon Islands with alarming frequency, and if the value of their teeth continues to increase, the motivation to harvest more could likewise increase. While the pantropical spotted dolphin is considered a species of “least concern” by the IUCN (the spinner is “data deficient”), that’s a classification that reflects the entire worldwide distribution of the species, not the local communities around the Solomon Islands. Recent evidence indeed suggests that cetaceans subject to human exploitation near other island communities form smaller, genetically isolated populations.

Still, the villagers are unlikely to cease their hunting again. “It was our impression that the people of Fanalei were puzzled by the attention they attracted in resuming the recent dolphin hunt,” write the researchers. They thought of their agreement with the Earth Island Institute as a brief lapse in a long, long history of hunting. The agreement created social tension in the village. Resuming the hunt created peace. On the bright side, the researchers felt that “the hunters were aware of, and willing to discuss, the conservation implications of over-exploitation.” They were aware, for example, of dolphin by-catch by local fisheries and saw it as a threat to their own way of life.

Are scientists and conservation advocates now at an impasse with the Lau people of Malaita who wish to hold on to their historical and cultural traditions? When scientific interests collide with cultural ones, the consequences can be messy. While they did not seem receptive to the idea of quotas or catch limits, they “could see the value of collecting scientific data that might help increase the probability that the drive hunting could continue in future generations.” That win may be minor, but it suggests a possible way forward at least in terms of conservation more generally, even if not in terms of the animal welfare concerns associated with drive hunting.

The researchers suggest that systematic record keeping effort be introduced to monitor all future hunts, and if possible, verification of numbers and of species through independent observers or at least through photographic documentation. They say that biological samples from each hunt ought to be collected and archived, as a means of both confirming species identifications and of tracking changes in diversity and population identity over time through genetic monitoring. Surveys should be done in the area as well, to estimate the abundance and diversity of dolphins in the Solomon Island more generally.

They add that alternative, non-lethal forms of dolphin interaction, such as dolphin watching tours and related ecotourism operations, could possibly reduce demand as well, at least for those dolphin hunters who are motivated primarily by economic interests. “Such [programs] could take advantage of the local knowledge and skills available in the communities as a result of drive hunting, providing a more sustainable future for both the dolphins and the cultural traditions of the hunters,” they say. – Jason G. Goldman | 06 May 2015

Source: Oremus M, Leqata J, Baker CS. 2015 Resumption of traditional drive hunting of dolphins in the Solomon Islands in 2013. Royal Society Open Science 2: 140524. DOI: 10.1098/rsos.140524.

Header image: Spinner dolphins via Teeth image via Oremus et al. (2015).